Engine help needed - 3.5L SOHC 1998 Gen 2.5

nwoods

Expedition Leader
When it comes to mechanical skills on engines and things.....I'm a pretty good rough carpenter :)

So today my son drove the Monty home from school (about 3 miles door to door), when he parked in the driveway, he heard the gush of liquids and some boiling steam coming out of the front end. He got out of the Monty, and the sure enough, the radiator purged its contents into the driveway....from somewhere under the engine.

When I got home this evening, I popped the hood to take a look. The top end of the radiator, and the overflow tank and discharge tubes were all dry. The upper and lower radiator hoses look okay and aren't super soft, and they are only a few years old, so I figure they are okay.

I couldn't look under the truck because of the skid plates, but when I looked a bit closer at the top end, I was shocked to SEE the timing belt!
This is the oddest thing I've ever seen..... kinda looks like the chain cut a perfect cutout from the face of the timing chain cover, like, super perfect. Like it was factory formed this way!
TIming_Belt-Cover-2560x1920.jpg


So I've never heard of anything that could make a timing belt jump like that and chew through the cover...I'm afraid to crank the engine over, though my son said it was running sweet and didn't notice anything until he heard the gurgling noises.

What can cause this? What does it mean? What is step one in repair? I am totally (and quite easily) stumped by this one.
Help!
 

nwoods

Expedition Leader
In discussing this more with my son, it seems that the Monty overheated the other day, and then suddenly it was fine..... sounds like classic water pump failure signs to me. So, assuming the water pump died, and started leaking into the timing belt area....what the heck would cause to chain the chew through the cover like that?
 

nckwltn

Explorer
Almost looks like the timing belt was sliding forward on the cam.

There isn't a forward stop on the cams, but there is on the water pump. If the pump was failing, it might have guided the belt forward due to the pump pulley being loose... thus pressing into back of the cover fallowing the belt to cut out a path.

Could also be the belt idler pulley on the driver's side.... pretty strange for Sure though!
 

evomaki

Observer
I think nckwltn is spot on. At the moment my timing assembly is off along with rockers for new valve stem seals, lash adjusters, timing assembly, etc. I've been looking at that area more than I care to. I think very likely to be exactly as he said, but pretty darn strange. Now you need to tell your kid (as I well might need to with mine) that when something mechanical has an issue, it is rarely, if ever, just fine again by itself. Better do something or say something.
 

RyanY

Adventurer
I'd say that it's time to tear down the front of the motor with intent to do the timing belt, water pump, and thermostat - possibly more depending on what you discover. Do you know when the timing belt was last replaced?
 

nwoods

Expedition Leader
I'd say that it's time to tear down the front of the motor with intent to do the timing belt, water pump, and thermostat - possibly more depending on what you discover. Do you know when the timing belt was last replaced?

About 2 years ago, less than 20,000 miles ago
 

RyanY

Adventurer
About 2 years ago, less than 20,000 miles ago

It sucks to have to be getting in there again so soon.

I'm assuming the water pump was changed at the same time? If it was then you know which brand of water pump to avoid from now on.

Some additional items to check and possibly replace when you've got it apart are the crank pulley bolt, tensioner pulley, and tensioner.
 

nwoods

Expedition Leader
Isn't there supposed to be an inspection cover there?

Is there? Can anyone corroborate that? If something just fell off, that would be awesome! Unfortunately, these covers are a devil to find. I found a lower cover in San Diego and the Upper right cover in Colorado. Parts: $100. Shipping: $115. ouch!
 

mr_ed

Toolbag
Is there? Can anyone corroborate that? If something just fell off, that would be awesome! Unfortunately, these covers are a devil to find. I found a lower cover in San Diego and the Upper right cover in Colorado. Parts: $100. Shipping: $115. ouch!

Just went out and checked on my '98 Gen 2.5...no inspection opening. Looks like your belt somehow installed that hole.


Sent while on the toilet using Tapatalk
 

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